The study of constrained Hamiltonian systems predates Dirac and Bergmann with
earlier work by Rosenfeld [1]}, [2]}. Like Rosenfeld, Bergmann and his collaborators [3]}, [4]}, [5]}, [6]}, [7]}, [8]} were focused on field theories like general relativity that are covariant with respect to
general four–dimensional coordinate
transformations.
Dirac took a more basic approach to the problem by considering a generic singular Lagrangian [9]}, [10]}, [11]}, [12]}, [13]}. He developed the algorithm for the case of systems with a finite number of degrees of freedom. His view was that the generalization to field theory, with an infinite number of degrees of freedom, would be “merely a formal matter".
